Yes, but now you're talking about a faulty driver, and one would not usually need a THD test to detect that.
That misses the point. If THD were any good then it should be able to tell a good driver from a bad one, but it can't. And you rely on this!?
I think you might be mixing up "efficiency" with "peak SPL capability"...
No I'm not.
If you send 2.83 volts to an 8 ohm sealed enclosure and it produces 90dB and I send 2 volts to an 8 ohm BP enclosure and it produces 90dB, then the BP is more efficient than the sealed enclosure. The BP speaker moved less to produce the same output, hence lower distortion too.
How much of a bandwidth do you need a SUBwoofer to play? Anything above 80hz is not a SUBwoofer anymore.
What kills me is the Pro Audio people and Audiophiles design so called SUBwoofers enclosures to play to 50hz. That's a BASS bin, not a SUBwoofer enclosure. If the lowest note of a piano is 27.5hz, then why design a so called SUBwoofer enclosure to play to 50hz???
Then I guess that you wouldn't consider them "subs". To me it's just semantics.
Im not crystal clear on this because the unversal label of TH/BP/TH with chamber volumes is a lot of different things and yet frequency is quickly the boss of them all. That ‘effciency’ reference is only obvious to a person who has an acoustically efficient enclosure with an electrically inefficient source of power to the device sending the signal. Once you take that situation to a level where it actually shows itself and reveals what might not be obvious the answer is unique.
you cant argue with an amp that keeps dropping into ‘protect’ at a certain frequency but never foes playing that same frequency if you hook up different enclosure to it. The akward thing as a human here is that the actual
Enclosure overall might seem louder in an area much more so then just the assumption of areas shown in a sim as electrical impedance.
Its 2021.... time to build a paraflex, a tapped pipe with driver just inside that mouth and plain qw pipe with the vent and direct radiator in a real place and time... ie: folded twice with the driver entry at the first fold.
I hope this makes sense, but its real: Now make all of those fair and represent nothing (including opinions and assumptions) except the use of the same driver TS parameters and there limits, the same long sections of pipe size used and the same exact interval of seperation between all things because each of them and there folds are a pipe. You must gold and entry at a defined point nothing else matters. Anyone who doesn't do exactly that has ruined any chance at arguing anything that can be shown as parts of any wave needed to help here??
suddenly things reveal REAL things and not made up assumptions...
Just for fun, put all that in a room thats got a pair of each of thise in it and and that is also sharing that pipe dimension ironically too 8foot x 8foot x 8foot is
real. And so is 15 hz tuned pipes , mid 30s tuned pipes, and 100 hz tuning on other pipes. But they all might share a common disaster at 100 or imagine that they dont, it all works out somehow???
I dunno, because i have yet to finish that entirely. but i only need two more 15 hz driver candidates to fill out that scenario yet and one more purchase of amp/powerstupply that can keep up with the needs of the elephant in room (no pun intended)
you cant hear what you cant see. thats reality. Because as soon as you see it whatever you hear changes if its not the same. Were human, not just an ear... that brain will screw you up and spit you out just to protect you! Lions and tigers and tapped pipes oh my!! Scary pipes!!? Theres more to see than suggest hear.And im taking the earl geddes approach to a lot of pipes and all of them share a unique pipe section. I dunno, but theres a lot of funny tings going on in pipes that are assumed sometiing ?
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That is absolutely right, people don't seem to understand context anymore these days.
Which is even more true with a multi-sub system.
(if not like a fundamental part of it, to be honest)
What would YOU call a SUPPOSEDLY low frequency enclosure that could NOT play the lowest note key of a piano?
I still say 50hz & up = bass bin and NOT SUBwoofer.
BTW, I have no issues with multiple subs. My argument is sealed is not better than BP4/BP6. And for those that don't know, a FLH is a BP4.
I still say 50hz & up = bass bin and NOT SUBwoofer.
BTW, I have no issues with multiple subs. My argument is sealed is not better than BP4/BP6. And for those that don't know, a FLH is a BP4.
I don't know, maybe "gobbledygook", does the name really matter?
My room can easily do 20 Hz with closed box gobbledygooks, it's all about the room response not some theoretical free field response.
You know that I wrote the original paper on BP enclosures defining all order from 4th through 8th and I used them extensively for many years. But that was pre DSP and with LF EQ it just doesn't matter what the design is as it all gets EQ'd and the subs with the most flexibility work out best.
I just call it a box with a transducer in it, that does a certain frequency range at a certain SPL with a certain distortion threshold. (and maybe with a certain directivity)
It's all heavily depended on context.
Not taking the subjective experience/psycho-acoustics and financial budget into consideration.
Without context or a certain use-case you can't say if something is better or not and even within a certain use-case there are so many more factors to make something "better" or "worse".
The only thing I can say about bandpass systems, is that I don't see many benefits anymore these days, with an abundance in cheap and accurate active filtering and amplification.
That's just pure practical.
It's all heavily depended on context.
Not taking the subjective experience/psycho-acoustics and financial budget into consideration.
Without context or a certain use-case you can't say if something is better or not and even within a certain use-case there are so many more factors to make something "better" or "worse".
The only thing I can say about bandpass systems, is that I don't see many benefits anymore these days, with an abundance in cheap and accurate active filtering and amplification.
That's just pure practical.
Hi - does anyone have experience using the 8" Rythmik drivers in this kind of configuration? They each need 0.7 sqft of vol for a sealed box...two drivers per amplifier....I don't know how far from the amp the driver can get (or what kind of tuning might allow distance). Nor do I know if you have to use their amp or if its possible to add the necessary circuitry to, say a rack mount style amp to run the speakers. Superficially, they would appear to provide a very small form factor and be capable of achieving a pretty broad range...any thoughts would be appreciated - Thanks!
Multiple subs is about technique, not specific implementations. It works in any situation and the specifics of individual sources are not really relevant unless they limit the source in some way that negates its use - such as a fixed LP filter and no EQ ability. With multiple subs you need flexibility.
gedlee "Multiple subs is about technique, not specific implementations. It works in any situation and the specifics of individual sources are not really relevant unless they limit the source in some way that negates its use - such as a fixed LP filter and no EQ ability. With multiple subs you need flexibility."
not trying to be too pedantic but aren't multiple subs still better even if you have limited EQ abilities, placement options etc.
not trying to be too pedantic but aren't multiple subs still better even if you have limited EQ abilities, placement options etc.
Thank you Dr. Geddes...
I've been through some of your interviews, white papers and this thread, so I think I have a decent grasp of the technique. I don't understand how the quality of the subs used affects the outcome...(I'm trying to blend with Raidho XT-1 which is a ribbon based satellite...many would describe as being very fast and rolls off at 80hz or so). My system is for music only. In your discussions you favor much larger subs than I would be able to use. I was going down the path of searching for subs with a small form factor but still having a reputation for detail articulation and range....this of course is attributed to a single sub...does it matter with multiple? Is it better to have one larger, more dynamic sub if possible and two small ones? Any thoughts on how to think about this would be appreciated. Thank you.
I've been through some of your interviews, white papers and this thread, so I think I have a decent grasp of the technique. I don't understand how the quality of the subs used affects the outcome...(I'm trying to blend with Raidho XT-1 which is a ribbon based satellite...many would describe as being very fast and rolls off at 80hz or so). My system is for music only. In your discussions you favor much larger subs than I would be able to use. I was going down the path of searching for subs with a small form factor but still having a reputation for detail articulation and range....this of course is attributed to a single sub...does it matter with multiple? Is it better to have one larger, more dynamic sub if possible and two small ones? Any thoughts on how to think about this would be appreciated. Thank you.